Rusty coolant

[datsun240z]

Dear S friends,
I'm cleaning the entire coolant system on my 280s as the coolant was very rusty. It seems that the car has been sitting at least 2 years before I bought it.
The inside of the swirl pot and the 2 coolant tubes (steel) are very rusty.
Is there a good way to clean and stop that rust? I'm worried about rust flakes going all over the cooling sytem and the water pump...
Cheers
Greg
from Brussels

[TvrJohn]

you could use a product called Rad Flush, then when you refill use anti freeze which includes a rust inhibitor

[glenrobbo]

If the inside of the steel tubes & the swirl pot are shedding large flakes of rust, I would be worried about them perforating and leaking in the near future. I recommend replacing them with new ones.
Try Tim at ACT products, or you could ask ShaunS3C on here if he could make you a nice stainless steel one.

If the rust is just a sludgy deposit, which dries to powder, then Radflush should help clean the system, and use a bottle brush to clean out the pipes & swirlpot.
It would be well worth removing the radiator and giving it a good long backflushing as well.

As said earlier, when you refill, use a good quality anti-freeze with corrosion inhibitors.

Best of luck with your 280S,
Glen

Edited by glenrobbo on Saturday 20th September 14:51

[Kitchski]

Use de-ionised water in the future too. Red antifreeze is better than blue, but don't mix them.

[datsun240z]

I have used phosphoric acid to convert and stop that rust in the pipes and swirl tank. The results are awesome.
I have now refilled the system with water and Wynns coolant flush.
What's the best way now to empty this mix and to replace it with a G12 coolant ? Is there a drain somewhere on the engine block ? (2800cc cologne)
Cheers !

[shake n bake]

Kitchski said:

Use de-ionised water in the future too. Red antifreeze is better than blue, but don't mix them.

I was under the impression red anti freeze is for modern engines only as it will eat away at rubbers or something on older engines?
I might be wrong but I'm sure one of the chaps at work said something along those lines!

[phillpot]

datsun240z said:

Is there a drain somewhere on the engine block ? (2800cc cologne)

This is a 2.9 block but quite possibly same or very similar?



Access might be quite tricky and there's every chance it will be a little tight!

Might be easier to just drop a hose or two off and flush through every way you can with a hose pipe?

shake n bake said:

Kitchski said:

Use de-ionised water in the future too. Red antifreeze is better than blue, but don't mix them.

I was under the impression red anti freeze is for modern engines only as it will eat away at rubbers or something on older engines?

Accoprding to this article from a well repected supplier here on PH, it's not as simple as choosing colour and it's the copper/brass radiator that could be a problem , not the rubber hoses (which I think are used on cars old and new).

datsun240z said:

replace it with a G12 coolant ?

I think that is an AOT "modern spec" anti-freeze, NOT suitable for your car (if you have original brass radiator and heater matrix) according to the Opie Olis article linked to above ????

Edited by phillpot on Monday 6th October 20:51

[Kitchski]

shake n bake said:

Kitchski said:

Use de-ionised water in the future too. Red antifreeze is better than blue, but don't mix them.

I was under the impression red anti freeze is for modern engines only as it will eat away at rubbers or something on older engines?
I might be wrong but I'm sure one of the chaps at work said something along those lines!

That did sound a bit too broad when I re-read it! Basically, the red stuff is ok with most stuff from 1990 onwards, so anyone running a really original example should approach with caution. It's not the rubbers, more the solders etc in the radiator or any traces of lead solder used in the engine (some water pumps used to contain it).
It's a better anti-freeze than the blue (ie more efficient) but yes, it's not compatible with all cars. Definitely not on classics!

[v8s4me]

Kitchski said:

..... the red stuff is ok with most stuff from 1990 onwards,...It's a better anti-freeze than the blue ....

According to the Opie Oils article...

"The different colours are non specific to the different types of antifreeze. The manufacturer can dye the product any colour they want."

So now that Roy has killed off the pressure cap saga will coolant colour be the new debate?

[Top Gear TVR]

I think Blue is faster. (i must get rid of the pink)

[Kitchski]

v8s4me said:

Kitchski said:

..... the red stuff is ok with most stuff from 1990 onwards,...It's a better anti-freeze than the blue ....

According to the Opie Oils article...

"The different colours are non specific to the different types of antifreeze. The manufacturer can dye the product any colour they want."

So now that Roy has killed off the pressure cap saga will coolant colour be the new debate?

The pressure cap debate is CLOSED? When did this happen?!

I'll re-phrase....the red we use is ok for most stuff after 1990! Always check the bottle!